Triplet Sum.py

# You have been given a random integer array/list(ARR) and a number X. 
# Find and return the number of triplets in the array/list which sum to X.

from sys import stdin


def findTriplet(arr, n, x):
    #Your code goes here
    #return your answer
    num = 0
    for i in range(n):
        for j in range((i + 1), n):
            for k in range((j + 1), n):
                if (arr[i] + arr[j] + arr[k]) == x:
                    num += 1
    return num


#Taking Input Using Fast I/O
def takeInput():
    n = int(stdin.readline().strip())

    if n == 0:
        return list(), 0

    arr = list(map(int, stdin.readline().strip().split(" ")))
    return arr, n


#main
t = int(stdin.readline().strip())

while t > 0:

    arr, n = takeInput()
    x = int(stdin.readline().strip())
    print(findTriplet(arr, n, x))
    t -= 1